That's when Johnson, of Hollywood, pulled out a handgun and shot Jhon, police say, sending patrons frantically scrambling near the store's exit at about 7:15 p.m.

Jhon, a retired corrections officer from New York City, was pronounced dead at Broward Health North. Police say Jhon, of Coral Springs, had gone to the Walmart, where he'd worked for three years, to shop with his wife.

After shooting Jhon, Johnson ran across North State Road 7 and, moments later, fatally shot himself in the head. A police dog helped investigators recover his body two hours later in the 500 block of Northwest 61 st Avenue.

"[Jhon] was a very outgoing, very helpful person and it wasn't unlike him to help someone out or help anybody out in need. Apparently that was what he was doing at the time," Lt. Gary Paquin said.

Jhon's, sister, Ursula Jhon, was distraught Saturday as she coped with the loss of her brother, who had worked as a corrections officer for 20 years.

"Right now I can't even think or talk," she said.

Jhon's neighbor, Raymond Wilkins, 68, lamented the death of a man who dreamed of opening a horse ranch for children, he said.

Jhon had also helped Wilkins get a job as a door greeter at the Walmart where the shooting happened. Although Wilkins worked there briefly, he was thankful to have a caring neighbor, he said.

"He was a good man. He was quiet, friendly, peaceful," Wilkins said, "He helped when he could."

A Margate police substation is located inside the Walmart, just feet away from where Jhon was killed. The substation is meant to deter shoplifters, but it is mainly manned when police are called to take suspects away.

"We do respond to Walmart almost daily for shoplifters. Whether they prosecute or not, it's a decision that they make," Paquin said.

A police sky tower, or elevated booth with surveillance equipment, also captures activity in the parking lot. On Friday, it captured an unidentified woman who had dropped off Johnson at the store drive off in a Mercedes- Benz.

Police have located and interviewed her, but have not charged her with any crimes linked to the killing. The homicide remains under investigation, Lt. Andy Zettek said.

Florida Department of Law Enforcement records show that Johnson had been convicted of a home burglary in Boca Raton and grand theft in Miami-Dade County.

A Golden Gate Estates, Florida man was arrested Monday after Collier County sheriff's deputies say he broke into a woman's house, left her love notes and took photos of himself with her underwear on his head.